Operating mechanism for a writing instrument



Dec. 23, 1958 L. c. HANSEN OPERATING MECHANISM FOR A WRITING INSTRUMENTFiled June 2z', 1954 2 Sheets-Sheet 1 iil' Dec. 23, 1958 L. c. HANSENOPERATING MECHANISM FOR A WRITING 1N Filed June 23, 1954 STRUMENT 2Sheets-Sheet 2 United States OPERATING `lVIECHANISlVI FOR yA WRITINGINSTRUMENT Lewis CfHansen, Fort Madison, Iowa, assignor to W. A.

Sheaifer Pen Company, Fort Wladimir, `Iowa, a cor- .poration of Delaware.Application Jne'zs, 1954, Serial No. 438,663 Claims. (Cl. `nos-42.03)

of-the instrument.

It is an important Object of this invention to pro-vide an improvedoperating mechanism fora writing instrument utilizing a single manuallyengageable means to eect both extension and retraction of-the writingunit.

Many oper-ating mechanisms for expelling and retracting a writingunitihave `heretofore .been pro-poed. Many of the devices `previously`proposed haveutilized a `plurality 0f actuating'buttons, onecustomarily functioning to lextend the writing 4unit and a secondfunctioning to release the writing unitfor retraction into .the barrelof theiristrument. Suchfa device using a plurality `of buttonsis.generallyinconvenient and confusing to the user. Preferablya-devicelutilizing a single push button for both extending andretracting the writing unitis employed.

Devices heretofore proposed utilizing a` single push button havegenerally employed various mechanical elements such as toggles orlevers, some of which rely uponthe gravitational effect for operation.Such devices utilizing pivotal parts, gravitational'force and the likehave generally proven unreliable and expensive to manufacture.

"Still other devices have `been proposed heretofore using asingle pushbutton in which thedegree .of depression determines the mode ofoperation; that is, if the push button is fully depressed the mechanismfunctions to retract the writing unit, while, if the push button is onlypartially depressedthe writing unit is expelled fo-rwardly into thewriting position. For positive and'easy operation of an actuatingmechanism it is vdesirable that a single psh button function `to extendand retract the writing unit on alternate depressions of the push buttonirrespective ofthe degree of motion thereof.

AIt is therefore a further object of this invention tozprovide animproved operating -mechanism for a writing instrument utilizing asingle push button for both extenLion and retraction of a`writing unit.

It is another object of this invention to provide an improved mechanismfor writing instruments in which a single push button may befullydepressed to effect alternate extensions and retractions of anassociated writing unit.

"It is still another object ofthis invention to provide an improvedmechanism v'for writing instrumentshaving no pivoted or rotatablymounted parts subjectto wear but utilizing only flat spring members andslidingparts.

It`is still another object 0f this invention to provide an improvedoperating mechanism for alternately moving an element between two"predetermined positions, said mechanism being completely self-containedpermitting utilization lwith any associated instrument irrespective ofthe natureJ thereof.

jIt is ^a^f`rther *object of this invention to 'provide animprovedoperating-lmechanism'A utilizing a^'flat yoke spring atentthe'writing unit includng a ballftype-writing ud applicator,

areservoir communicating therewith-and a plunger 'mechanism havingamanually engageable rearwardly i extended.

free end for effecting movement of the writing unitlwithin the barrel. Acoilispring disposed between thereserv'oir and the barrelnorm'allyiurgesthe writing unit to thefretrac-ted position. The i plunger unit has anoperating mechanism `associated therewith which `includesa formed springof flat material normally carried in tixed relationship tothe reservoirand having a yoke-like portion, one leg-of-which isdixed `with respecttothe axis of the reservoir and the other leg of which is formed`withahook member normally Aurged voutwardly into engagement with thebarrel. `An annular lip or shoulder is formed on the inner surface ofthe barrelffor engagement by the hook member tomaintainthe writing unitin theextendedwriting position. The spring yoke and operating plungerare soorientedithatthe plungerengages the'bight portion of the .springon alternatefdepressions of the plungerwhereby the free leg of the yokeand the associated hoolcmernber are Vurged inwardlytoward the=axis ofthewriting unit andoutof engagement withthe annular shoulder formedinzthebarrel. `rl`h'us,asucc`essive depressionsof the operating plungercause alternate extensions-and `retractions of the writingunit.

For amore complete understanding of this invention referencewill nowbemade to the accompanying drawings wherein:

Fig. 1 isanillustratio-nin longitudinal section of one embodimentiofthis invention with the writing unit in the retracted position;

`Fig. 2 illustrates the embodimentof Fig. l1 with the writingunit'inthe` extended or writingposition;

Fig. 3 `illustrates :the embodiment of Fig. `1 with `the Writing unit inan overextended position which the unit normally 4assumes immediatelyYprior to being1placedvin thewriting position ofFig. 2;

iFig. 4 illustrates the embodimentof Fig. v1 with Athe Writing lunit inthe overextended position which it assumes during a retractingcycle` ofoperation;

Fig/5 ris latransverse sectional View taken alongthe line S-Sof Fig. 1,showingthe disposition of the elements'in the retractedposition;

Fign is a'transversesectional view taken along-the line 6--6 of Fig. 2showing the elementsin the writing position;

Fig. 7 isa top plan view of the plunger and actuator portion of theembodiment of Fig. l;

Fig 8 is a bottom plan view` of the plunger and actuator -portionof theembodiment ofFig. 1; and

rFig. 9 is an` exploded view of the plunger and actuator mechanismshowingthe various parts thereof in disassembled and alignedrelationship.

Referring now to the drawings and more particularly to Fig.l1, a writinginstrument li() is illustrated comprising generally a barrel 12 and awriting unit `14 slidably mounted therein and urged rearwardly into saidbarrel by a coil spring 16. The writing unit 14 includes a reservorl anda feed tube 20 terminating in a.;ball applicator 22. VHowever,writing.units of various `designs maybe incorporated in a writing instrumentvconstructed in accordance with `this invention.

"Thecoil spring1`6 is compressed between a shoulder Q 24 formed in thebarrel 12 and the forward end 26 of the reservoir. The rearward end ofthe reservoir 18 abuts against an actuating mechanism 28 in such amanner that the reservoir may be removed from the barrel with easewithout the removal of the actuator or any of the associated elements.The actuating mechanism 28 includes a plunger 30 having a hollowcylindrical portion 32 Vinto which an apertured plug 34 fits. The plug34 is continuously urged forwardly out of the cylindrical opening 32 bya coil spring 36. For reasons which will become obvious from thedescription to follow, the coil spring 36 must be less stiff than thespring 16 so that the pressure of the plunger 30 will first compress thespring 36 before producing axialv motion of the writing unit 14. Ashaped spring 38 formed from at sheet spring material has a portionthereof secured in an aperture 40 in the plug 34. As shown in Fig. l andalso in Fig. 9, the spring 38 has an N shape and one linee or bightportion 42 of the N spring is secured in the aperture 40. One end of thespring 38 has a right angle bend 44 formed therein and engageable in anaperture 46 formed in the plunger 30. This prevents free motion andspecially rotation of the spring 38 with respect to the plunger 30. Theother free end of the N spring 38 is formed with a hook-like member 48which is normally urged outwardly into engagement with the inner surfaceof a rearward portion 50 of the barrel 12. The rearward portion 50 ofthe barrel 12 is threadably engaged with the body portion 52 thereofwhereby the parts may be readily disassembled for easy replacement ofthe writing unit. The rearward portion 50 of the instrument may beenclosed in a metal sheath 56 having a pocket clip S8 secured thereto ina conventional manner.

Upon depressing the plunger 30 the hook 48 will engage a shoulder 54 onthe inner surface of the rear portion 50 of barrel 12 and will thus lockthe writing unit in the extended position.

The operation of this device will be clear from a consideration of thesequence of operations illustrated in Figs. l, 2, 3 and 4. In Fig. l thewriting instrument is' shown in the retracted position in which the hook48 is in sliding engagement with the inner surface of the barrel portion50 and the ball point 22 is retracted inside of the barrel portion 52.As shown in Fig. 3, upon corni pletely depressing the plunger 30 thehook 48 slides along the inner surface of barrel portion 50 a distancesufficient to permit the hook to extend beyond the shoulder 54. In thisposition the ball point 22 is overextended beyond the forward end ofbarrel portion 52 and a shoulder 60 on the fluid feed may engage thecorresponding shoulder 62 in the barrel portion 52. The latterengagement is not required, however, for operation of the mechanism.During the extension of the writing unit the coil spring 36 will becompletely compressed as a result of its less stiff character ascompared to coil spring 16. Thus, the plug 34 will be moved into thecylindrical opening 32 and the forward end 64 of the plunger 30 will abuthe rearward end of the reservoir 18.

Upon release of plunger 30 the parts will assume the positionsillustrated in Fig.' 2. Therein it can be seen that the ball point unit22 has retracted somewhat` from the position illustrated in Fig. 3 toassume a lnormal writing position. In so doing the hook 48 has engagedthe annular shoulder 54 to lock the N spring 38 against any furtherrearward movement. As the knee 42 of the N spring is in engagement withthe rearward'end of reservoir 18 and the N spring 38 has suicientlongitudinal rigidity to withstand the rearward force of spring 16, thereservoir and consequently the entire writing unit 14 are restrainedagainst further rearward motion. However, because of the lateralresiliency of the N spring 38 and the compression of the coil spring 16,a bow is formed in the center leg 66 of N spring 3 8 causing the freebight portion 68 of N spring 38 to move outwardly toward the innersurface of barrel portion 50. When mand ual pressure is completelyrelieved on plunger 30, the rearward bight portion 68 of spring 38 isfree to move outwardly to the position illustrated in Fig. 2. As clearfrom a comparison of Figs. 3 and 4, the distortion of leg 66 alsoresults in an effective rotation of the bight portion 68. Consequently,the direction in which the outer leg of spring 38 extends is shiftedtoward the axis of the writing instrument, Depending upon the exactdesign of the unit and the proportional stiffness between the varioussprings, the reservoir 18 may move rearwardly a suiicient distance sothat the rear end thereof will engage the hook portion 48 of spring 38.This engagement produces a rigid lock to prevent further rearwardmovement. However, the apparatus of this invention willfunctionsatisfactorily whether or not this abutting relationship existsprovided only that sufficient travel is produced so that the center leg66 is bowed and the l bight portion 68 moved outwardly a predeterminedamount. n

The purpose of the outward shifting of the bight por-V tion 68 will beclear from a consideration of Fig. 4. In' Fig. 4 the plunger 30 has beendepressed to overextend the ball point 22 in a manner similar to thatdescribed with respect to Fig. 3, However, as shown in Fig. 4 theimmediate history of the unit shows that the unit wasA in the writing orextended position and the bight 68 0fl spring 38 shifted outwardly andeffectively rotated. Thus, upon depressing plunger 30 a detent portion70 thereof engages the bight 68, frictonally locking it in the outwardlyshifted and rotated position whereby the hook 48 is urged inwardly awayfrom the shoulder 54 formed inv the barrel portion S0. Upon release ofhook 48 the en-l tire internal portion of the writing instrument isfree.

" to move rearwardly relative to the barrel 12 under thev influence ofcoil spring 16. Coil spring 16 will effect rearward movement of thewriting unit and plunger to a lposition in which the hook 48 is disposedrearwardly of annular shoulder 54. Upon further rearward motion ofplu-nger 30 the right angle iiange 44 on the free leg of N spring 38engages rear shoulder 45 of the rear-y ward portion S0 of barrel 12stopping the rearward rnove-V ment of the writing unit, Plug 34 carriedby the writingl unit also stops, permitting coil spring 36 to expandcausing additional rearward motion of plunger 30, moving the detent 70rearwardly relative to spring 38 and permitting the bight portion 68 tomove inwardly and count-V er-rotate, once again assuming the positionshown in Fig. l. This will permit the hook portion 48 of N spring 38 tomove outwardly into engagement with the inner surface of barrel portion50. The unit is now in the retracted condition initially described withrespect to Fig. l and is prepared for subsequent actuation to thewriting posi? tion by a complete depression of plunger 30. Thus,successive depressions of plunger 30 will cause the hook member 48 toalternately engage and disengage the shou1-' der 54 and likewise saidsuccessive depressions of plunger 30 will produce alternatedisengagements and engage-` ments of the bight portion 68 of N spring 38with thel forward detent portion 70 of the plunger 30.

The motion of the hook 48 is clearly shown in Figs. 54 and 6. In Fig. 5the hook 48 is shown frictionally en-` gaging the inner surface ofrearward portion 50 of barrel, 12. In Fig. 6 the writing unit is in theextended posi-vl tion and the hook 48 is in engagement with the shoulder54 formed on the inner surface of barrel portion 50.. The assembly andconstruction of the various elementsr of the plunger unit are clearlyshown in Figs. 7, 8 and 9. Therein it can be seen that the plunger 30has a longitudinal diametric groove 72 cut in the forward portionthereof to receive the N spring 38. The forward end of, the plunger 30also has a cylindrical bore 32 to receive plug 34 which is apertured toreceive the knee portion. 42 of the N spring 38. The hook 48 extendsoutwardly from the longitudinal groove 72 to engage the inner surface ofthe barrel (not shown), jIhe coil 36is comt pressed between theforwardend `of `the central portion of plunger 30 and the rear end of plug 34normally urging plug 34 outwardly `from the cylindrical bore 32.However, a `right angle flange 44 is formed on the free leg of N spring38 to engage the aperture 46 in the plunger to limit the relative motionbetween the plunger and the plug and N spring,

While various modifications will be manifest to one skilled in thewriting `instrument art, it is believed clear that applicant herebyteaches a novel means for actuating a writing unit in which a singlepush button may be successively depressed to produce alternateextensions and retractions of the writing unit in an associated barrel.Moreover, a novel system of actuation is disclosed which is positive inoperation, inexpensive to construct and possesses along useful life.

Without further elaboration, the foregoing will so fully explain thecharacter of my `invention that others may, by applying currentknowledge, readily `adapt the same for use under varying conditions ofservice, while retaining certain features which may properly be said toconstitute the essential items of novelty involved, which items areintended `to be defined and secured to me by the following claims:

I claim:

l. In a writing instrument having a barrel portion and a writing unittherein axially movable between a forward writing position and aretracted position, means for alternately maintaining said unit in eachof said positions comprising resilient means urging said unit to theretracted position, an axially and manually shiftable operating elementrearwardly of said unit within said barrel portion, yoke spring meanswithin said barrel having a bight portion disposed rearwardly thereinand operatively engageable with said operating element and two forwardlyextending longitudinally rigid laterally yieldable legs, hook meansformed in one of said legs and normally urged outwardly toward saidbarrel portion, the other of said legs being operatively associated withsaid unit and restrained against substantial lateral movement, andshoulder means disposed in said barrel portion to receive said hookmeans when said operating element and said unit are manually moved tosaid forward position and released whereby the force of said resilientmeans on said other leg moves said bight portion outwardly and urgessaid hook means inwardly when said hook means is in engagement with saidshoulder means, said hook means being held against inward movement byengagement with said shoulder means said operating element, whensubsequently manually depressed, engaging said bight portion in theoutward position to maintain said bight portion in the outward positionand release said hook means from said shoulder means to permit inwardmovement thereof.

2. In a writing instrument having a barrel portion and a writing unittherein axially movable between a forward writing position and aretracted position, means for alternately maintaining said unit in eachof said positions comprising resilient means urging said unit to theretracted position, an axially and manually shiftable operating elementrearwardly of said unit within said barrel portion, yoke spring meanswithin said barrel having a bight portion disposed rearwardly thereinand operatively engageable with said operating element and two forwardlyextending longitudinally rigid laterally yieldable legs, hook meansformed in one of said legs and normally urged outwardly toward saidbarrel portion, the other of said legs being operatively associated withsaid unit and restrained against substantial lateral movement, shouldermeans disposed in said barrel portion to receive said hook means whensaid operating element and said unit are manually moved to said forwardposition and released, and a resilient member urging said operatingelement and said unit apart and having less stiffness than saidresilient means, the force of said resilient means on said other legmoving said bight portion outwardly and urging said hook means inwardlywhen said hook means is in engagement with said shoulder means, saidhook means being held against inward movement by engagement with saidshoulder means, said operating element when subsequently manuallydepressed, engaging said bight portion inthe outwardposition to maintainsaid bight portion in the outward position and release `said hook meansfrom said shoulder means to permit inward movement thereof.

3. In a writing instrument having a barrel portion, a writing unittherein axially movable between a forward writing position and aretracted position and resilient means urging said unit to saidretracted position, said unit including a fluid dispenser and areservoir in axial alignment, an actuating mechanism contained in `saidbarrel portion and in free abutting relationship with said reservoircomprising an operating element operatively aligned with said unitwithin said barrel portion, said operating element having a manuallyengageable portion extending from the rearward end of said barrelportion and a forward portion operatively engageable with said unit,spring means in said barrel portion having a `transversely yieldablelongitudinally extending leg portion having its forward end operativelyengaging said unit, said leg portion extending between said unit andsaid operating element, said spring means further having a transverselymovable portion extending from the rearward end of said leg and normallyurged outwardly toward said barrel portion, shoulder means formed insaid barrel portion to receive said transversely movable portion whensaid unit is moved to the forward position whereby said unit ismaintained in said forward position, said longitudinally extending legportion being distorted transversely by the force of said resilientmeans, said distortion urging said transversely movable portion inwardlyfrom said shoulder whenever said transversely movable portion is inengagement with said shoulder, said transversely movable portion beinglheld against inward movement by engagement with said shoulder means,said operating element having a formed portion adjacent the rearward endof said leg portion and engageable with the rearward end of said legportion to maintain said longitudinally extending leg portion sodistorted when so distorted upon subsequent forward and substantialrearward movement of said operating element, said transversely movableportion being free for inward movement from said shoulder upon saidsubsequent forward movement.

4. In a writing instrument having a barrel portion, a writing unittherein axially movable between a forward writing position and aretracted position and resilient means urging said unit to saidretracted position, said unit including a fluid dispenser and areservoir in axial alignment, an actuating m'echanism contained in saidbarrel portion and in free abutting relationship with said reservoircomprising yoke spring means within said barrel having a bight portiondisposed rearwardly therein and operatively engageable with saidoperating element and two forwardly extending longitudinally rigidlaterally vyieldable legs, hook means formed in one of said legs andnormally urged outwardly toward said barrel portion, the other of saidlegs being operatively engageable with said unit in abutting end to endrelationship and restrained against substantial lateral movement, andshoulder means formed in said barrel portion to receive said hook meanswhen said operating element and said unit are manually moved to saidforward position and released whereby the force of said resilient meanson said other leg moves said bight portion outwardly and urges said hookmeans inwardly when said hook means is in engagement with said shouldermeans, said hook means being held against inward movement by engagementwith said shoulder means, said operating element when subsequentlymanually depressed, engaging said bight por tion in the outward positionto maintain said bight portion in the outward position and release saidhook means from said shoulder means to permit inward movement thereof.

5. In a writing instrument having a barrel portion, a writing unittherein axially movable between a forward writing position and aretracted position and resilient means urging said unit to saidretracted position, said unit including a uid dispenser and a reservoirin axial alignment, an actuating mechanism contained in said barrelportion and in free abutting relationship with said reservoir comprisingyoke spring means within said barrel having a bight portion disposedrearwardly therein and operatively `engageable with said operatingelement and two forwardly extending longitudinally rigid laterallyyieldable legs, hook means formed in one of said legs and normally urgedoutwardly toward said barrel portion, the other of said legs beingoperatively engageable with said unit in abutting end to endlrelationship and restrained against substantial lateral movement, andshoulder means formed in said barrel portion to receive said hook meanswhen said operating element and said unit are manually moved to saidforward position and released, plug means abutting the rearward end ofsaid reservoir and apertured to frictionally receive said other 8 vleg', and a resilient member between said' element and said plug meansof less stiffness than said resilient means whereby initial forwardmovement of said operating element compresses said resilient member, theforce of said resilient means on said other leg moving said bightportion outwardly and urging said hook means inwardly when said hookmeans is in engagement with said shoul der means, said hook means beingheld against inward movement by engagement with said shoulder means,said operating element, when subsequently manually de-v pressed,engaging said bight portion in the outward posi tion to maintain saidbight portion in the outward posi'-` tion and release said hook meansfrom said shouldermeans to permit inward movement thereof.

References Cited in the le of this patent t UNITED STATES PATENTS 1378,897 Myers Mar. 6, ,1888 2,398,548 Moore Apr. 16, 1946.' 2,584,569Frentzel Feb. 5, 1952 FOREIGN PATENTS v 809,514 Germany July 30, 1951v

